• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.1 no.1
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• pp.61-67
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• 1997

The effects of Insect growth regulator Dimilin which interfere with the synthesis of chitin in the cuticle of insect larvae were investigated at various concentrations using the copepod larvae of Tigriopus japonicus Mori. The larvae were cultured at control, 1, 5, 10, 20, 50, and 100 ppb Dimilin solutions and three replicate experiment were carried out to give correct analysis. Lethal effects of Dimilin on larvae of T. japonicus occurred above 1 ppb Dimilin solution after 8 days. $LC_{50}$ of larvae was 50 ppb Dimilin on the 4th day. Lethal effects of Dimilin on adults or T. japonicus occurred above 20 ppb Dimilin solution after 13 days. $LC_{50}$ of adults was 50 ppb Dimilin on the 12 days. Egg viability has little relation to Dimilin solution concentrations.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.10a
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• pp.451-458
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• 2002

This paper presents the prediction of deep excavation-induced ground surface movements using artificial neural network, which is of prime importance in the perspective of damage assessment of adjacent buildings. A finite element model, which can realistically replicate deep-excavation-induced ground movements was employed and validated against available large-scale model test results. The validated model was then used to perform a parametric study on deep excavations with emphasis on ground movements. Using the result of the finite element analysis, Artificial Neural Network(ANN) system is formed, which can be used in the prediction of deep exacavation-induced ground surface displacements. The developed ANN system can be effecting used for a first-order prediction of ground movements associated with deep-excavation.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.194-205
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• 2009

In geotechnical engineering, the mechanical characteristics of soil, the main material of geotechnical engineering, is highly related to the confining stress. Reduced-scale physical modeling is often conducted to evaluate the performance or to verify the behavior of the geotechnical systems. However, reduced-scale physical modeling cannot replicate the behavior of the full-scale prototype because the reduced-scale causes difference of self weight stress level. Geotechnical centrifuges are commonly used for physical model tests to compensate the model for the stress level. Physical modeling techniques using centrifuge are widely adopted in most of geotechnical engineering fields these days due to its various advantages. In this paper, fundamentals of geotechnical centrifuge modeling and its application area are explained. State-of-the-art geotechnical centrifuge equipment is also described as an example of KOCED geotechnical centrifuge facility at KAIST.

• International Commerce and Information Review
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• v.9 no.3
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• pp.161-180
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• 2007

The electronic bill of lading system replacing with traditional paper B/L has been evolved from SeaDocs and CMI to Bolero system. Therefore e-B/L is considered as an evolving concept rather than fixed one because it has been changed with development of information technology. Bolero system designed to replicate all functions of a paper B/L has some limitation to be utilized as an e-B/L in changing international business arena because it has a centralized model. Therefore it is considered to be important that the current e-B/L operating system needs to be diversified. This paper aims to provide three types of the operating model of global e-B/L to be applied with feasible solution coping with the current problems, which is expected to contribute to the utilization of electronic bill of lading.

• Structural Engineering and Mechanics
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• v.31 no.4
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• pp.423-437
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• 2009

In order to perform a step-by-step force-displacement response analysis or dynamic time-history analysis of large buildings with masonry infilled R/C frames, a continuous force-deformation model based on an equivalent strut approach is proposed for masonry infill panels containing openings. The model, which is applicable for degrading elements, can be implemented to replicate a wide range of monotonic force-displacement behaviour, resulting from different design and geometry, by varying the control parameters of the model. The control parameters of the proposed continuous model are determined using experimental data. The experimental program includes fifteen 1/3-scale, single-story, single-bay reinforced concrete frame specimens subjected to lateral cyclic loading. The parameters investigated include the shape, the size, the location of the opening and the infill compressive strength. The actual properties of the infill and henceforth the characteristics needed for the diagonal strut model are based on the assessment of its lateral resistance by the subtraction of the response of the bare frame from the response of the infilled frame.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.24 no.68
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• pp.31-36
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• 2001

Prior to the Independent Visual Background(IVB) luminance control experiment, we studied that IVB could reduce the simulator sickness depending on subject＇s knowledge about the IVB (expectation group) or non-IVB (no expectation group). As results of experiments from 12 subjects, expectation group＇s RSSQ scores were similar, no matter IVB was present or not. However, non-expectation group＇s RSSQ scores were lower when the IVB were present. The result from this experiment confirms the findings of Duh (2001), that an IVB may alleviate SS. However this effect was found only at the expectation group. Failure to replicate Duh＇s results could be due to several factors, such as individual differences in response to the IVB and the low number of subjects (n=6) in the no expectation group.

• Journal of muscle and joint health
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• v.4 no.2
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• pp.249-261
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• 1997

The purpose of this study was to explore the effect of short term selp-help education on pain, depression, self-efficacy, and quality of life in patients having chronic arthritis. This program was carried out 3 hrs per week for 4 weeks by 3 small groups among 10 patients. Research design was a quasi-experimental study of nonequivalent control group pretest-posttest design. The subject of this study were 10 of experimental group and 10 of control group. Before and after 4 weeks program, quality of life, self-efficacy, depression, pain, ADL were measured. As a result, it was confirmed the self-help education was effective to increase quality of life, but self-efficacy, depression, pain, ADL were not improved. This suggests the replicate study to examine the effect of self-help education with the large samples of subjects having chronic arthritis.

• Journal of Environmental Science International
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• v.1 no.1
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• pp.61-67
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• 1992

The effects of insect growth regulator Dimilin which interfere with the synthesis of chitin in the cuticle of insect larvae were investigated at various concentrations using the copepod larvae of Tigriopus japoniu Mori. The larvae were cultured at control, 1, 5, 10, 활, 50, and 100 pub Dimilin solutions and three replicate experiment were carried out to give correct analysis. Lethal effects of Dimilin on larvae of T japoniu occurred above 1 ppb Dimilin solution after 8 days. LC50 of larvae was 50 ppb Dimilin on the 4th day. Lethal effects of Dimilin on adults of T. japoniu occurred above 1 ppb Dimilin solution after 13 days. LC50 of adults was 50 ppb Dimilin on the 12 days. Egg viability has little relation to Dimilin solution concentrations.

• Journal of Environmental Science International
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• v.25 no.5
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• pp.745-748
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• 2016

Ninety ducks (one-day-old Pekins, 45 males and 45 females) were used to evaluate the effects of supplementing diets with Houttuynia cordata powder on the fatty acid profiles of duck breast meat. The ducks were allotted to one of the three treatment diets using a completely randomized design, each treatment-group containing three replicate pens with ten birds each (five of each gender). The experimental diets were: 1) Control (basal diet), 2) T1 (Control+ 1% Houttuynia cordata) and 3) T2 (Control+2% Houttuynia cordata). In spite of significant difference, the addition of Houttuynia cordata resulted in higher unsaturated fatty acid and lower saturated fatty acid contents than in the Control group. However, no remarkable difference was observed between 1% and 2 % Houttuynia cordata groups for fatty acid profiles.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.4
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• pp.511-519
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• 2010

This paper presents the modeling and validation of a pile-driver breech fatigue testing system model to replicate actual high pressure in a large caliber gun barrel. A hysteresis damping function was incorporated in the nonlinear impact force model. Test of real pile-driver breech fatigue testing system had been performed for model validation. Comparison of the experimental result and model simulation during impact were made. Numerical studies were performed to evaluate how the actual chamber pressure pattern in the live firing of gun barrel was affected by parameters' variation. Some of the parameters simulated included input velocity, damping coefficient and stiffness. As a result, a variety of actual chamber pressure pattern could be reproduced and controlled through current simulation model.